阅读说明：本技术 一种基于聚电解质为模板的纳米凝胶的制备方法 (Preparation method of nanogel based on polyelectrolyte as template ) 是由 王俊有 丁鹏 郭旭虹 马蒂恩·A·科恩·斯图尔特 于 2019-12-02 设计创作，主要内容包括：本发明涉及一种基于聚电解质为模板的纳米凝胶的制备方法,在聚电解质溶液中,加入相反电荷的单体,以及交联剂,引发剂,调节溶液pH至电中性,然后对反应体系抽充氮气除氧,引发聚合得到纳米凝胶复合物。用无机盐溶液超滤、离心或透析除去纳米凝胶复合物中的模板,即可得到所需纳米凝胶。收集滤液,透析除去无机盐,即可回收聚电解质模板,进行重复使用。这种纳米凝胶的制备方法简单,结构,尺寸和带电性质可控,且模板可循环利用,在纳米材料,药物传输和缓控释,以及生物成像等领域具有广泛的应用前景和研发价值。(The invention relates to a method for preparing a nanogel based on polyelectrolyte as a template, which comprises the steps of adding monomers with opposite charges, a cross-linking agent and an initiator into a polyelectrolyte solution, adjusting the pH value of the solution to be electrically neutral, pumping nitrogen into a reaction system to remove oxygen, and initiating polymerization to obtain a nanogel compound. And removing the template in the nanogel compound by using inorganic salt solution for ultrafiltration, centrifugation or dialysis to obtain the required nanogel. And collecting the filtrate, dialyzing to remove inorganic salt, and recovering the polyelectrolyte template for reuse. The preparation method of the nanogel is simple, the structure, the size and the charged property are controllable, the template can be recycled, and the nanogel has wide application prospect and research and development value in the fields of nanomaterials, drug delivery, sustained and controlled release, biological imaging and the like.)

1. A preparation method of a nanogel based on polyelectrolyte as a template is characterized by comprising the following steps: adding monomers with opposite charges, a cross-linking agent and an initiator into a polyelectrolyte solution, adjusting the pH of the solution to be electrically neutral, then pumping nitrogen into a reaction system to remove oxygen, and initiating polymerization to obtain a nanogel compound; removing the template in the nanogel compound by using an inorganic salt solution for ultrafiltration, centrifugation or dialysis to obtain the required nanogel;

collecting filtrate, dialyzing to remove inorganic salt, and recovering the polyelectrolyte template which can be repeatedly used;

the polyelectrolyte template is a homopolymer or a block polymer;

when polyelectrolyte with positive charges is used as a template, the used monomer has negative charges, and the synthesized nanogel has negative charges;

when polyelectrolyte with negative charges is used as a template, the used monomer has positive charges, and the synthesized nanogel has positive charges.

2. The method of claim 1, wherein: the homopolymer polyelectrolyte template is one or more of polyacrylic acid, poly (2-acrylamide-2-methylpropanesulfonic acid) sodium, poly (styrene) sodium sulfonate, poly (dimethylaminoethyl methacrylate), poly (methacryloyloxyethyl trimethyl ammonium chloride) or poly (2-aminoethyl methacrylate).

3. The method of claim 1, wherein: the block polymer electrolyte template is one or more of polyacrylic acid-polyethylene glycol, poly 2-acrylamide-2-sodium methyl propane sulfonate-polyethylene glycol, sodium poly styrene sulfonate-polyethylene glycol, poly dimethylaminoethyl methacrylate-polyethylene glycol, poly methacryloyloxyethyl trimethyl ammonium chloride-polyethylene glycol or poly 2-aminoethyl methacrylate-polyethylene glycol.

4. The method of claim 1, wherein: the monomer with negative charges is acrylic acid, methacrylic acid, 2-acrylamide-2-methyl sodium propane sulfonate or sodium p-styrene sulfonate; the monomer having a positive charge is 2- (dimethylamino) ethyl methacrylate, 2-aminoethyl methacrylate, methacryloyloxyethyltrimethylammonium chloride, benzylethyltrimethylammonium chloride, N- [ (3-dimethylamino) propyl ] acrylamide, N- [ (3- (dimethylamino) propyl ] methacrylamide, ethyl 2- (dimethylamino) acrylate, (3-acrylamidopropyl) trimethylammonium chloride, N, N, N-trimethyl-3- (2-methylallylamido) -1-propylammonium chloride or acryloyloxyethyltrimethylammonium chloride.

5. The method of claim 1 or 2 or 3 or 4, wherein: the polyelectrolyte and monomer have a charge concentration of 5-500 mM.

6. The method of claim 1, wherein: the cross-linking agent is one or more of N, N ' -methylene bisacrylamide, ethylene glycol dimethacrylate, polyethylene glycol diacrylate, N, N ' -bis (acryloyl) cystamine or N, N ' - (1, 2-dihydroxyethylene) diacrylamide.

7. The method according to claim 1 or 6, characterized in that: the crosslinking agent is 1-50 mol% of the monomer amount.

8. The method of claim 1, wherein: the initiator is a photoinitiator or a thermal initiator.

9. The method of claim 8, wherein: the photoinitiator is one or more of 2-hydroxy-2-methyl-1-phenyl-1-acetone, 2-hydroxy-4' - (2-hydroxyethoxy) -2-methyl propiophenone and lithium phenyl-2, 4, 6-trimethyl benzoyl phosphinate; the thermal initiator is persulfate or a water-soluble azo compound.

10. The method of claim 1, 8 or 9, wherein: the reaction time is that the photoinitiator initiates polymerization for 1 to 12 hours under the illumination of an ultraviolet lamp or at the temperature of 70 ℃ by a thermal initiator.

11. The method of claim 10, wherein: the amount of the initiator is 0.1 to 10 wt% based on the amount of the monomer.

12. The method of claim 1, wherein: the inorganic salt is one or more of sodium chloride, potassium chloride, sodium nitrate, potassium nitrate, sodium sulfate or potassium sulfate.

13. The method of claim 12, wherein: the concentration of the inorganic salt is 0.1-5 mol/L.

14. A nanogel prepared according to the method of claim 1, wherein: the diameter of the nanogel is 50-400 nm.

Technical Field

The invention relates to a novel method for preparing nanogel, in particular to a method for preparing nanogel particles by using polyelectrolyte as a template and performing polymerization-induced self-assembly in one step, belonging to the technical field of novel materials.

Background

The nanogel is used as a class of nano-sized particles with a physical or chemical cross-linked polymer network structure, has the advantages of high internal water content, good stability, strong loading capacity, good biocompatibility and the like, and shows wide application prospect in the fields of nano materials, drug delivery, sustained and controlled release, biological imaging and the like. However, the synthesis of nanogel is mostly based on the microcapsule environment constructed by systems such as emulsion, microemulsion and inverse emulsion using surfactant, and the like, and the nanogel is prepared by initiating polymerization and then removing the used surfactant through dialysis. The method is widely applied at present, but a stable emulsion system depends on the use of a large amount of surfactants, so that not only is the waste of resources and the pollution to the environment caused, but also a series of problems are brought to the subsequent separation and the application of materials.

Polymerization-induced self-assembly, as a new method for preparing a high molecular structure, has attracted extensive attention of researchers in the aspects of synthesis and self-assembly of block polymers, efficient preparation of polymer nano materials and the like. The method utilizes the characteristic that the polymerization of the monomer is carried out to form the polymer and the polymer assembly is carried out simultaneously, not only can prepare high molecular assemblies with different structures by a one-step method, but also can carry out induced self-assembly under the condition of high concentration, and the advantage can not be achieved by the traditional self-assembly method.

As a functional macromolecule with charges, polyelectrolyte has unique advantages in aspects of macromolecule assembly, material preparation and the like in recent years. Compared with the traditional self-assembly of amphiphilic blocks, the self-assembly of polyelectrolyte has the following specific advantages: the assembly units are water-soluble, and organic solvents are not needed; the assembly is based on electrostatic interaction between charges of polyelectrolytes, and the structure and the properties of an assembly can be adjusted by adjusting factors such as the structure, the chain segment length, the charging property, the charge ratio and the ionic strength of the polyelectrolytes.

Disclosure of Invention

The invention adopts a new method, namely, the charged polyelectrolyte is taken as a template, the nano gel particles are prepared by polymerization-induced self-assembly in one step under the coexistence of monomer, cross-linking agent and initiator, and the template can be separated and recovered from the synthesized nano gel for repeated use. The preparation method is simple, the structure, the size and the charged property are controllable, the template can be recycled, and the preparation method has wide application prospect and research and development value in the fields of nano materials, drug delivery, sustained and controlled release, biological imaging and the like.

In order to achieve the purpose, the invention provides the technical scheme that:

a method for preparing nano gel based on polyelectrolyte as template includes adding monomer with opposite charges, cross-linking agent and initiator to polyelectrolyte solution, regulating pH value of solution to be neutral, pumping nitrogen gas to remove oxygen to reaction system, and initiating polymerization to obtain nano gel compound. And removing the template in the nanogel compound by using inorganic salt solution for ultrafiltration, centrifugation or dialysis to obtain the required nanogel. And collecting the filtrate, dialyzing to remove inorganic salt, and recovering the polyelectrolyte template for reuse.

Wherein, the polyelectrolyte template can be a homopolymer or a block polymer, and can be positively or negatively charged. The polyelectrolyte template of the homopolymer is polyacrylic acid, poly-2-acrylamide-2-methyl sodium propane sulfonate, sodium poly-styrene sulfonate, poly-dimethylaminoethyl methacrylate, poly-methacryloyloxyethyl trimethyl ammonium chloride and poly-2-aminoethyl methacrylate. The block polymer electrolyte template is polyacrylic acid-polyethylene glycol, poly 2-acrylamide-2-methyl sodium propane sulfonate-polyethylene glycol, poly sodium styrene sulfonate-polyethylene glycol, poly dimethylaminoethyl methacrylate-polyethylene glycol, poly methacryloyloxyethyl trimethyl ammonium chloride-polyethylene glycol, poly 2-aminoethyl methacrylate-polyethylene glycol.

When polyelectrolyte with positive charges is used as a template, the used monomers have negative charges, the monomers are acrylic acid, methacrylic acid, 2-acrylamido-2-methyl sodium propane sulfonate and sodium p-styrene sulfonate, and the synthesized nanogel has negative charges; when polyelectrolyte with negative charge is used as a template, the used monomer has positive charge, the monomer is 2- (dimethylamino) ethyl methacrylate, 2-aminoethyl methacrylate, methacryloxyethyl trimethyl ammonium chloride, benzyl ethyl trimethyl ammonium chloride, N- [ (3-dimethylamino) propyl ] acrylamide, N- [ (3- (dimethylamino) propyl ] methacrylamide, 2- (dimethylamino) ethyl acrylate, (3-acrylamidopropyl) trimethyl ammonium chloride, N, N, N-trimethyl-3- (2-methylallyl amido) -1-propyl ammonium chloride, and acryloyloxyethyl trimethyl ammonium chloride, and the synthesized nanogel has positive charge.

Wherein the polyelectrolyte and monomer have a charge concentration of 5-500 mM.

Wherein the initiator is a photoinitiator or a thermal initiator, and includes but is not limited to 2-hydroxy-2-methyl-1-phenyl-1-acetone, 2-hydroxy-4' - (2-hydroxyethoxy) -2-methyl propiophenone, lithium phenyl-2, 4, 6-trimethyl benzoyl phosphinate, persulfate and water-soluble azo compounds.

Wherein the crosslinking agent includes, but is not limited to, N, N ' -methylenebisacrylamide, ethylene glycol dimethacrylate, polyethylene glycol diacrylate, N, N ' -bis (acryloyl) cystamine, N, N ' - (1, 2-dihydroxyethylene) bisacrylamide.

The innovation point of the invention is that a novel preparation method is adopted to prepare the nano gel particles, namely, the nano gel particles are prepared by polymerization induced self-assembly in one step under the coexistence of a monomer, a cross-linking agent and an initiator by taking polyelectrolyte as a template.

Drawings

FIG. 1 is a graph showing the particle size distribution of nanogels of different sizes obtained from the preparation.

FIG. 2 is the nuclear magnetic hydrogen spectrum (a) of the nanogel after the elution of the template in example one, and the nuclear magnetic hydrogen spectrum (b) of the template are compared.

FIG. 3 is a comparison of the infrared spectra of the template and nanogels before and after elution of the template.

FIG. 4 is a TEM image (a) of the nanogel after metal loading, and an ultraviolet spectrophotometer spectrum of the nanogel loaded with the metal for catalyzing and degrading p-nitrophenol.

Detailed Description

The present invention will be further described with reference to the following examples.